Colorectal Cancer Screening for the Serrated Pathway

Area of Science:

• Gastroenterology
• Colorectal Cancer Research
• Pathology

Background:

• Serrated polyps are a group of colorectal lesions including hyperplastic polyps (HPs), sessile serrated adenomas/polyps (SSAs/SPs), and traditional serrated adenomas (TSAs).
• While all share serrated crypts, differentiating HPs from SSAs/SPs is diagnostically difficult.
• SSAs/SPs and TSAs are considered precursors to colorectal cancer, with SSAs/SPs potentially developing dysplasia over time.

Purpose of the Study:

• To review the classification and diagnostic challenges of serrated polyps.
• To highlight the progression of SSAs/SPs to colorectal cancer.
• To discuss optimal management strategies including detection, resection, and surveillance.

Main Methods:

• Review of current literature on serrated polyp classification and diagnosis.
• Analysis of pathological features distinguishing different serrated polyp types.
• Evaluation of endoscopic detection and resection techniques.
• Summary of surveillance guidelines for various serrated polyp subtypes.

Main Results:

• Distinguishing HPs from SSAs/SPs based on morphology is challenging, despite shared serrated features.
• TSAs exhibit cytologic dysplasia, while SSAs/SPs can progress to develop dysplasia.
• The flat and pale appearance of some serrated polyps complicates endoscopic detection.
• Endoscopic mucosal resection (EMR) offers higher complete resection rates.

Conclusions:

• Accurate classification of serrated polyps is essential for appropriate patient management.
• SSAs/SPs and TSAs require close surveillance due to their malignant potential.
• EMR is recommended for complete removal of concerning serrated polyps.
• Surveillance recommendations vary based on polyp type, size, and presence of dysplasia.